Finally SI have included the youth quality in the editor. I just went through it quickly and explains why Brazil have absolute great regens all the time and the rest not so much. Also says something about how much SI value the Dutch and English compared to Spain, France, Italy and Germany. (Hint, Holland and to lesser extent England are far underrated IMO )
They create regens based on a number ranging from 0-200, 0 being terrible and 200 being Lionel Messi every year. Highlight the spoiler for the most common and/or surprising nations. You can check other nations in the editor.
France - 158
Ivory Coast -107
Czech Republic -95
San Marino -29
Some really strange surprises for me. Some nations are ranked way higher or lower than you would imagine.
IMO Holland is ranked way too low in comparison to other teams. If you look at the Dutch footballing history it has achieved far more for the quality of regens it gets.